fancy-regex breaking changes
Every breaking API change we have recorded in fancy-regex on crates.io: 3 breaking changes in 1 version. Below are its newest version, removals and renames first, each with its source.
Newest change October 24, 2026
On this page
0.20.0
- Behavior changed
In Unicode mode, \xHH escapes above 0x7F match the Unicode codepoint encoded as UTF-8 rather than a raw byte, so patterns such as \xFF now match ÿ. Bytes modes are unchanged. github.com - Behavior changed
delegate_dfa_size_limit
The option now limits the lazy DFA cache capacity instead of the fully compiled DFA size limit, so limits tuned under the old meaning may behave differently. github.com - Behavior changed
Regex.capture_names
capture_names now reports the name for every group declared with the same name, and named backreferences resolve to the last group with that name. Code that assumed one group per name may see different results. github.com
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